Rest Energy of Electrons in Particle Accelerators: Zero or Not?

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Electrons in a particle accelerator reach a speed of 0.999c relative to the laboratory. Is the rest energy of the electron equal to zero?
 
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The kinetic energy of an electron (or anything else, for that matter) at rest is zero.

The total energy of the electron, calculated from ##E=\gamma{m_0}c^2## or ##E^2=(m_0c^2)^2+(pc)^2"##, is .511 511 MeV when the electron is at rest and greater when it is moving and the kinetic energy is non-zero.

[Edit - left the decimal point out the first time around]
 
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Mizies said:
Is the rest energy of the electron equal to zero?

The rest energy of an electron is 0.511 MeV, regardless of how fast it is moving.
 
Nugatory said:
The kinetic energy of an electron (or anything else, for that matter) at rest is zero.

The total energy of the electron, calculated from ##E=\gamma{m_0}c^2## or ##E^2=(m_0c^2)^2+(pc)^2"##, is 511 MeV when the electron is at rest and greater when it is moving and the kinetic energy is non-zero.

.511MeV or 511keV bro, 511MeV is some ginormous electron.
 
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Matterwave said:
.511MeV or 511keV bro, 511MeV is some ginormous electron.
:)
 
Matterwave said:
511MeV is some ginormous electron.

It's overweight even for a muon. :oldruck: